Backport stand-alone sample PR 5

https://github.com/Azure-Samples/ms-identity-python-daemon/pull/5/files

Author: rayluo

sample/confidential_client_certificate_sample.py

@@ -67,7 +67,7 @@
     graph_data = requests.get(  # Use token to call downstream service
         config["endpoint"],
         headers={'Authorization': 'Bearer ' + result['access_token']},).json()
-    print("Graph API call result: " + str(graph_data))
+    print("Graph API call result: %s" % json.dumps(graph_data, indent=2))
 else:
     print(result.get("error"))
     print(result.get("error_description"))